Method of and apparatus for sensitizing paper



S. B. DAVENPORT EI'' AL METHOD OF AND AEPARATUS FOR SENSITiZING PAPER File d March 3, 1934 2 Sheets-Sheet 1 Aug. 25, 1936. s. B. DAVENPORT ET AL 2,051,826

METHOD OF AND APPARATUS FOR SENSITIZING PAPER Filed March 5, 1934 2 Sheets-$heet 2 fnz/erzz bnsj oflney" Patented Aug. 25, 1936 PATENT OFFICE METHOD OF AND APPARATUS FOR SENSITIZING PAPER Schuyler B. Davenport, Bound Brook, and Alfred Savio, Dunellen, N. J.

Application March 3, 1934, Serial No. 713,930

4 Claims. (Cl. 91-10) is invention relates to a method of and apparatus for sensitizing roto-gravure carbon tissue.

. It is an object of this invention to thoroughly sensitize the gelatine of roto-gravure carbon tissue and in doing so, maintain the paper backing of the carbon tissue in a perfectly dry state during the entire operation in order that a sheet of carbon tissue sensitized through the teachings of this invention will dry in a very short time. This is a great advantage over the known methods where the entire sheet of carbon tissue is submerged in a sensitized bath of bichromate solution and then squeegeed on a ferrotype plate by hand. Uniformity of pressure throughout the surface of the tissue cannot be had by this method and the sensitizing solution cannot be evenly distributed over the surface of the carbon tissue.

In those instances where carbon tissue constitutes the basic material for the printing of carbon prints from a positive film, whether it is pictorial or design work, a plurality of carbon prints may be printed from one individual positive film and the result in the succeeding production will be uniformly perfect and, in this connection, an unusual number of such prints can be made from one positive, as compared with known methods.

It has been found in practice withthis invention that the timing of the sensitizing machine can be so arranged that the gelatine coating of the carbon tissue becomes softened by the bichromate sensitizing solution so that the best results are attainable as the carbon tissue and the ferrotype plate are conveyed through the machine, for as the bichromate solution is delivered 5 in a flowable state between the ferrotype plate and the gelatine coating of thejcarbon tissue at a suitable temperature, ithas a tendency to soften the gelatine coating of the carbon tissue in order that it willladhere to the ferrotype plate. The carbon tissue after the foregoing treatment -is permitted to dry in order that it may be removed from the ferrotype plate and'the gelatine coating of the carbon tissue which was of a dull finish before it was sensitized now has a highly glazed surface finish, which latter condition is the ideal state for satisfactory results in its use, and since the sensitized solution of each carbon tissue is a previously'unused solution, the sensitized solution is clean and free of foreign elements or substances.

- This is in contrast to the known methods where a great number of carbon sheets are subjected to the sensitizing solution contained in one tray.

When so many sheets are subjected to the contents of a single tray, certain particles of dirt are dislodged from the carbon tissue and find their way into the sensitizing solution and these foreign substances are to a greater or lesser extent imbedded in the gelatine coating of the carbon tissue, and furthermore a certain amount of the 5 gelatine coating of the carbon tissue is dislodged from the carbon tissue and finds its way into the sensitizing solution, which afiects the efficiency of the gelatine coating in the roto-gravure art.

With the foregoing and other objects in view, 10 the invention. consists in the details of construction and in the arrangement and combination of parts to be hereinafter more fully set forth and claimed.

In describing the invention in detail, reference 15 will be had to the accompanying drawings forming part of this application, wherein like characters denote corresponding parts in the several views, and in which- I Figure 1 illustrates a plan view of (a machine 20 embodying the invention;

Figure 2 illustrates a view in elevation of one end thereof 2 I Figure 3 illustrates a view in elevation of the other end thereof; 25 Figure 4 illustrates a view in front elevation;

and

Figure 5 illustrates an enlarged detail sectional view of fragments of the machine on approximately the line 5-5 of Figure 1 with those parts 30 of the machine beyond the section line omitted.

In these drawings i0 denotes a suitable frame in whicha motor II is mounted, the said motor being preferably electrically driven and supplied with current through an appropriate conductor 35 I2. A pinion I3 is in mesh with a gear wheel M on a shaft IS, the said shaft being joumaled in the frame in any appropriate way and having on its end opposite the gear wheel ll a pinion Hi meshing with a gear wheel II on a shaft l8. The shaft 40 I8 also has a pinion l9 meshing with the gear wheel 20 on a shaft 2|. By'reason of the use of the gearing l1, l9 and 20, the r. p. m. of the shaft 2| is reduced as compared with the r. mm. of the drive shaft and the drum or roller 22 on the shaft is driven slowly.

Brackets 23 and 24 extend rearwardly from the frame and they are provided with a plurality of apertures such as 25 in which a pivot 26 applied to each bracket may be adjusted. An arm 21 50 having a slot-28 is applied to each pivot and a nut 29 threaded on a pivot serves to frictionaliy engage the arm and hold it in different positions of adjustment. The apertures '25 and slots 28 'permit a relatively wide range of adjustment of a table 30 whose outer end is supported by the arms. it being shown that each arm is connected to the table by a pivot 3|. The inner end of the table is supported on the periphery of the drum and receives the ferrotype plate and paper issuing from the machine as will presently appear.

The paper in its unsensitized state but having the gelatine coating is curled in a roll and as an initial step in the operation, one end of the paper is attached to the front end of the plateby adhesive tape or some other appropriate means and the advanced end of the plate and paper are applied to the drum at the'top thereof. A roller 32 engages the drum and the plate and paper are gripped therebetween by imparting to the drum an intial turning movement sumcient to start the plate and paper between the drum and roller 32 and the remainder thereof rests in the trough 33 which is carried by suitably supported arms such as 34. Arms 35 and 36 are .oscillatively mounted on pivots carried by the brackets 23 and 24 and a shaft 31 is journaled in the said arms 35 and 36. The roller 32 is mounted on the shaft 37 and extensions 38 of the shaft constitute hand grasps by which the arms 35 and 36 are forced outwardly so that the periphery of the roller 32 is out of engagement with the drum for since the roller is preferably rubber jacketed, the Weight of the roller will tend to cause the periph-' cry of the roller to become fiat if it is allowed to rest onthe drum when not in operation.

In order to hold the paper in place and to guide it between the drum and roller, standards 39 and 40 are attached to the arms 35 and 36 and they extend upwardly at the ends of the roller. Arms 4| and 42 are pivotally connected to the standards 39 and 40 respectively and rubber jacketed rollers 43 are journaled therein, the peripheries of said rollers being in engagement with the periphery of the roller 32 or with paper interposed between the same, for when the machine is set for operation and the end of the paper has been attached to the end of the plate, the paper will lie between the rollers 32 and 43 and extend rear wardly thereof.

In order to impart the initial motion to the' drum for clamping the plate and paper between the drum and roller 32, the shaft, I5 is provided with a hand wheel 44 and by manually operating the hand wheel; the drum is turned and the plate particular requirements.

A tank as for holding sensitizing solution is supported on the post or standard 41 in a'plane. above the machine so that the sensitizing solution will fiow by gravity to the plate. In order to coat the plate with the sensitizing solution, the tank is provided with a faucet 48 to which a hose 49 is connected, the said hose'having a nozzle 50 so that by manipulating the nozzle, the sensitizing solution may be discharged on the plate preferably at the junction of the plate and paper as the two are being brought into superimposed relation by the action of the drum and roller.

The foregoing method of sensitizing, the paper may be repeated with each sheet, it being understood that the sheets are of certain Well known commercial size.

After a plate and the paper have been passed between the drum and theroller, the plate is forced out on the table 30 from whence it can be removed. The inclination of the table can be regulated by the adjustment of the arms 21 which adjustment will compensate for the flowable character of the sensitizing solution and prevent its 40 and projects beyond said standards to formstops 52 which are engaged by the arms 42 b which the said arms are held elevated.

A holding rod 53 is carried by arms 54 pivote on the standards 39 and 40, the said holding rod being movable into cooperative relation with the roller .32 to guide the paper as it is being moved when the roller is rotated. The arms 54" may be held by springs such as 55 which are conventionally shown.

While the invention is directed to the coating of what is known as carbon tissue, in the description, this stock has been referred to as carbon tissue or "paper, by which terms the inven-. tors wish to be understood as comprehending any basic material which is to receive a sensitizing solution for use in the photo-engraving art.

We claim:

1. The method of sensitizing roto-gravure carbon tissue consisting in attaching one end of a carbon tissue to an end of a ferrotype plate, interposing the superimposed plate and tissue between rollers, driving the rollers to cause the rollers to move the plate and tissue therebetween, guiding the tissue into cooperative relation with the ferrotype plate, and depositing a sensitizing solution on the said plate substantially at the location where the tissue and plate are contacted.

v2. The method of'sensitizing roto-gravure carbon tissue consisting in holding one end of a carbon tissue in engagement with a ferrotype plate between feeding rollers, holding the remainder of said tissue and the plate out of contact one with the other, applying a sensitizing solution in the space between the tissue and plate at their point of contact when moving, and in rotating the rollersto feed theplate and tissue therebetween.

* 3. In an apparatus for sensitizing roto-gravure carbon tissue, a suitably driven roller, a roller mounted to coact with the first mentioned roller,

suitably mounted rollers engagiiigthe periphery of the second mentioned roller operative to draw carbon tissue around the second mentioned roller and guide it to a location between the first and second mentioned rollers, a ferrotype plate engageable with the advanced end of the said carbon tissue interposed between the first and second mentioned rollers, and means for depositing a sensitizingsolution between theplate and tissue as it is transferred through the apparatus by the said rollers.

4. In an'apparatus for sensitizing roto-gravure carbon tissue, a suitably driven roller, a roller mounted to engage the periphery of the first mentioned roller and operative therewith, pivotally mounted arms in operative relation to the mentioned roller for guiding tissue therebetween,

the said arms terminating in proximity to the coacting portions of the first and second mentioned rollers, a terrotype plate having an end of the carbon tissue attached to it interposed between the first and second mentioned rollers, and means for depositing a'sensitizing solution at approximately the junction of the plate and tissue as they are brought into operative relation with each 5 other.

SCHUYLER B. DAVENPORT. AIJ'BED SAVIO. 

